While the military has taken steps to reduce tobacco use for the past two decades, 26.9% of new military recruits report regular tobacco use prior to enlistment,7 and 28.5% of Airmen report regular use one year into service. The prevalence of tobacco increases in Airmen?s first year in the Air Force despite a ban on tobacco during the first 10 weeks of training and 63.0% of Airmen being ?completely confident? they will remain tobacco free one year later.7 What is most troubling is the high rate of initiation among never users. Within the first year of Air Force service, 20.4% of never users initiate regular tobacco use and 67.0% of former users re- initiate, and 76.2% of this use occurs during Technical Training. These high rates of initiation/re-initiation are occurring despite the fact that there are rigorous anti-tobacco regulations on all Department of Defense military bases, suggesting that there is something unique about the Technical Training environment leading to this initiation/re-initiation. To date, no studies have assessed the impact of the tobacco built environment in this ?natural experiment? of forced abstinence and rapid relapse. In addition, no studies have measured the influence that Technical Training leadership, including Commanders, Military Training Leaders, and Technical Training Instructors, have on Airmen?s behavior during Air Force Technical Training. Informed by the Social Ecologic Model, the Specific Aims of this Early Stage Investigator project are to: (1) Refine existing measures to determine knowledge, attitudes, beliefs and behaviors related to tobacco use among Airmen, Military Training Leaders and Instructors (Phase 1). During Year 1, conduct focus groups with Airmen, Military Training Leaders and Instructors at the 5 largest Air Force Technical Training schools (Lackland AFB, Fort Sam Houston, Keesler AFB, Sheppard AFB, and Goodfellow AFB) to inform the adaptation and development of measures. (2) Determine the influence of Airmen?s, Military Training Leaders? and Instructors?, and Commanders? knowledge, attitudes, beliefs and behaviors related to tobacco use on Airmen?s tobacco use during Technical Training (Phase 2). Beginning in Year 2, survey 10,000 Airmen at the beginning and end of Technical Training, survey 200 Military Training Leaders and 190 Instructors, and conduct interviews with all base Commanders as they turnover throughout the study at 5 Technical Training schools (N=102). (3) Determine the impact of the tobacco built environment (e.g., number, density, proximity of tobacco retail outlets, tobacco availability, pricing, placement, and promotion) both on and around the base perimeter on Airmen?s tobacco use (Phase 2).